Spray nozzles



Aug. 27, 1957 J, u BETE SPRAY NOZZLES Filed April 13, 1956 mm ATPWRA FX R o m E V N I Jo'bw. a 5572' United States Patent SPRAY NOZZLES John U. Bete, Greenfield, Mass., assignor to Beta Fog Nozzle, Inc., a corporation of Massachusetts Application April 13, 1956, Serial No. 578,076

4 Claims. (Cl. 299114) This invention relates to spray-type nozzles and is directed particularly to spray-type nozzles for producing a finely atomized liquid spray or fog.

An object of this invention is to provide a spray nozzle that has a high degree of atomization of the liquid discharged from the nozzle.

Another object of the invention is to provide a spray nozzle that does not clog.

Another object of the invention is to provide a spray nozzle with a high degree of atomization that is formed as a single piece and is resistant to deformation.

Another object of the invention is to provide a spray nozzle that provides a uniform spray of atomized droplets.

Another object is to provide a spray nozzle that is compact and inexpensive to manufacture.

Another object of the invention is to provide a spray nozzle that is rugged in construction and capable of being made from plastic materials.

Another object of the invention is to provide a spray nozzle that produces a narrow, angle, cone-shaped spray of highly atomized droplets.

Other and further objects of the invention will be apparent from the following description taken in connection with the drawings in which:

Fig. 1 is a side view of the nozzle;

Fig. 2 is another side view of the spiral vane of the nozzle at ninety degrees to the side view of Fig. 1;

Fig. 3 is a sectional view of the fitting and nozzle taken along lines 3-3 of Fig. 4;

Fig. 4 is an axial interior end view of the nozzle;

Fig. 5 is a sectional view taken along lines 55 of Fig. 1;

Fig. 6 is a sectional view taken along lines 66 of Fig. 2;

Fig. 7 is a side view of another embodiment of the invention; and

Fig. 8 is an axial interior end view of the nozzle shown in Fig. 7.

In Figs. l4 a nozzle 10 comprises a tubular portion 11 forming a passage 12 and a helical-shaped vane 13 extending axially from the tubular portion 11. The vane 12 forms a helical slot 14 and has an inner wall 15 defining a bore 16 for delivering water from the passage 13 throughout the vane for discharge through the slot 14. The vane spirals inwardly and the wall 15 has an inward axial taper to form the bore 16 in a conical or bullet shape so that the cross section of the bore is reduced in the direction of flow through the nozzle.

The vane 13 has a helical surface 18 extending at an angle to the axis of the nozzle radially outwardly from the bore 16. The surface 18 extends from the tubular portion if to the surface 19 forming an edge 20 therewith. The surface 19 has a helical shape and extends outwardly at a greater angle to the axis than the surface 18. The surface 19 extends from the surface 18 to the end surface 21 at the tip of the nozzle. The nozzle has 2,804,341 Patented Aug. 27, 1957 "ice a cylindrical exterior surface 24 and a helical surface 25 forming the exterior surface around the outside of the vane 13 and tapered axially inward to form the nozzle in an outer cone shape. The surface 25 terminates at the surface 19 to form an edge 21. The tip of the nozzle has a surface 26 in the same conical plane as the surface 25 and forms with the surface 19 an exterior edge 27.

On the under side of the vane 13 there is a helical surface 28 forming an upper wall of the slot 14. The slot 14 between the surfaces 18 and 28 remains substantially uniform in cross section up to the line 20. The cross section of this passage is illustrated in Fig. 5. The surface 19 is at a greater angle to the radial plane, as illustrated in Fig. 6, to provide a full cone spray.

The surface 18 forms with the wall 15 an inner helical edge 31. The pitch of the edge 31 remains substantially uniform throughout the nozzle and spirals inward with the taper of the wall 15. The wall 15 forms an edge 32 with the surface 28. With the increase in pitch of the surface 19, the pitch of the edge 32 correspondingly increases so that the width of the wall 15 is axially reduced as its extends axially towards the end of the nozzle.

In viewing the nozzle axially through the passage 12, the inner wall 15 spirals inwardly with the wall at an angle so that the wall 15 has a component facing the stream of water entering the nozzle. The surface 18 spirals inwardly so that in extending axially towards the end of the nozzle, an increasing area of the surface 18 projects radially inward from the axially preceding wall portion. The surface 19 similarly projects inwardly from the axially preceding wall portion. The inner edge 31 terminates at an end portion 33 to form a plug at the end of the nozzle so that the water at the end of the nozzle is discharged over the surface 21. The liquid entering the nozzle first engages the upper portion of the edge 31 which extends radially inwardly of the cylindrical wall because of the curved taper of the wall 15. The curved tapering of the wall 15 and the tapering of the spiral of the surfaces 18, 19 present a continuous deflecting surface in the path of the water to peel off a sheet of water. The reduction in the cross sectional area of the bore by the curved taper of the wall 15 maintains the water as a homogeneous mass and reduces the turbulence or disintegration of the mass into separate portions. Thus throughout the length of the nozzle a uniform sheet of water may be peeled off by the vane 13 and atomized to form droplets.

The terminating spiral surface 19 is a complete turn between the edge 20 and the surface 21 so that the water, reaching the end of the nozzle, forms a complete finite conical sheet to eliminate any breaks in the spray. The reduction of the conical shape of the wall 25 reduces the width of the surfaces 18, 19 and thereby reduces the metal to liquid contact and the frictional losses of the admission of the water from the nozzle. This reduction in the outside diameter increases the atomization of the water and increases the efficiency of the nozzle.

In Figs. 7 and 8 another embodiment of the invention is shown in which the vane 41 has a tighter spiral. The surfaces 42, 43 are formed so that the edge 44 is inward of the inner edge 45 formed by the wall 46 of the bore and the helical surface 47. With this arrangement the spray has a more forward component so that it is shaped in the form of a cone having the major portion of the spray Within thirty degrees of the central axis of the nozzle. The edges 44, 45 are formed so that radially there is no overlapping. The wall 46 has a curved taper reducing the turbulence within the nozzle and providing a uniform sheet of liquid to be peeled off by the surface 42.

The above described nozzles have the particular advantageous features of providing a clear and open passage for the liquid to flow through. There are no obstructive elements in the bore or passages of the nozzles to become clogged with sediment carried by the liquid. The spiraling of the deflecting surface inwardly into the path of the water in the bore produces a continuous sheet of Water around the nozzle which disintegrates into a spray of uniform size droplets. The curved taper of the bore additionally contributes to the uniform distribution of the spray around the nozzle. The surfaces 18, 19 and 42 of the vanes in the various embodiments are preferably straight to permit the free and unobstructed discharge of the liquid through the helical slot. The width of the vane is reduced by tapering the exterior surface of the nozzle. In addition to the improved performance, the nozzle has the additional mechanical features of ruggedness and compactness. The vane does not need to be made of a great number of spirals to produce a desired uniformly distributed spray. One or two turns are all that i necessary, depending on the particular configuration that is desired. Also the open inner passages and the width of the helical slot provide for an easy and inexpensive machining of the nozzle. The end of the vane has a member for supporting the nozzle during the machine operation.

Various other modifications and changes will be made in the foregoing embodiments without departing from the invention as set forth in the appended claims.

I claim:

I. A nozzle for producing a spray of desired characteristics directed outwardly around an axis comprising a generally tubular member having a passage for conveying a liquid, at vane formed in the shape of a helix axially converging in the direction of flow and having a helical slot for discharging liquid from the nozzle, said vane having an inner helical axially curved wall to form a curved tapered bore for receiving liquid from said passage and delivering liquid to said slot and maintaining a smooth even flow to the end of the nozzle.

2. A nozzle for producing a spray comprising a helical vane having an upper radial surface to form a helical slot and having an inner helical curved longitudinal surface at an angle to the axis of said nozzle and of gradually reduced diameter in direction of flow to form an axial curved, tapered bore inside of said vane to reduce the cross section of said bore in the direction of flow, said upper surface having a portion inward of said axial preceding curved wall so that a continuous helical surface faces axially to peel a portion of the liquid passing through the bore and discharge it through the helical slot to form a spray.

3. A nozzle for producing a spray comprising a vane formed in an axially tapered helix with an inner longitudinal curved surface at an angle to the axis and tapering inward to form a curved tapered bore inside of said vane, said vane having an upper radially extending helical surface spaced to form a helical slot for discharging liquid and forming with said longitudinal surface a helical edge of progressively reduced diameter to position a portion of said upper surface radially inward from the axially preceding curved wall to peel a portion of the liquid and discharge the liquid through the opening.

4. A nozzle for producing a spray as set forth in claim 3 in which said upper surface forms an outer edge with the outer surface of said helix, said outer edge having a radius less than the corresponding portion of the preceding turn so that the liquid discharged from said nozzle has a major portion of the spray with an angle less than thirty degrees to the central axis.

References Cited in the file of this patent UNITED STATES PATENTS 556,610 Ashton Mar. 17, 1896 1,246,355 Thomas Nov. 13, 1917 2,518,116 Bcte Aug. 8, 1950 2,612,407 Betc Sept. 30, 1952 

